Comparison for Corrosion Properties of Super 13Cr and High Strength 15Cr Martensitic Stainless Steels in Acid Solution

Comparative live acid (10%HCl+1.5%HF+3%HAc+5.1% TG201 inhibitor) experiment of corrosion resistance and matching ability of acidizing corrosion inhibitor in severe working environments of super 13Cr and high strength 15Cr martensitic stainless steels were investigated through high temperature and high pressure tests.The results show that the uniform corrosion rate of super 13Cr and high strength 15Cr martensitic stainless steel in severe working environments were 14.551 6 mm·a-1 and 13.495 4 mm·a-1 respectively, and those were far lower than standard specifications and requirements. Acidizing corrosion inhibitor displayed a good matching ability with super 13Cr and high strength 15Cr martensitic stainless steels, but appearance of pitting could not be fully prevented by adding acidizing corrosion inhibitor, and the pitting rate and pitting density of super 13Cr were greater than high strength 15Cr martensitic stainless steel. The corrosion resistance of high strength 15Cr martensitic stainless steel in live acid was better than that of the super 13Cr steel.